//C:10.12:stacker.cpp -- testing the Stack class
#include <ctype.h>
#include <iostream>
#include <cctype> // or ctype.h
#include "stack.h"

int main(void)
{
    using namespace std;
    Stack st; // create an empty stack
    char ch;
    unsigned long po;
    cout << "Please enter A to add a purchase order,\n"
         << "P to process a PO, or Q to quit.\n";
    while(cin >> ch && toupper(ch) != 'Q')    
    {
        while(cin.get() != '\n')
        {
            continue;
        }
        if(!isalpha(ch))
        {
            cout << '\a';
            continue;
        }
        switch (ch) 
        {
            case 'A':
            case 'a':
                cout << "Enter a PO number to add: ";
                cin >> po;
                if(st.isfool())
                {
                    cout << "stack already full\n";
                }
                else 
                {
                    st.push(po);
                }
                break;
            case 'P':
            case 'p':
                if(st.isempty())
                {
                    cout << "stack already empty\n";
                }    
                else
                {
                    st.pop(po);
                    cout << "PO #" << po << " popped\n";
                }
                break;    
        }
        cout << "Please enter A to add a purchase order,\n"
             << "P to process a PO, or Q to quit.\n";
    }     
    cout << "Bye\n";
}